As thousands of people prepare to join this year's Pride parade through central London, BBC News takes a look at some of the most striking images from the event's 45-year history.

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The first official UK Gay Pride Rally was held in London on 1 July 1972. The date was chosen as it was the nearest Saturday to the anniversary of the Stonewall riots of 1969, which saw people protest against a police raid at the Stonewall Inn, a gay bar in Manhattan.

In 1976, a picnic was held in Victoria Gardens by the Houses of Parliament during what was then called Gay Pride Week.

The march in 1996 saw gay men make a statement about religious attitudes to homosexuality by impersonating the Pope and members of the Mafia.

This year's parade is set to be the biggest yet, with more than 300 groups marching and more floats taking to London's streets than ever before. There will also be for the first time a seated grandstand - tickets for which have already sold out.

Image copyrightSteve EasonImage copyrightPeter Cade

The 2017 theme is Love Happens Here - and marks 50 years since homosexuality was decriminalised in the UK.

Pride in London has issued advice for those planning to attend: "We recommend you come ready for a day of exciting parade watching.